MRSA Is Culprit in Higher Hospitalization Rate

Methicillin-resistant Staphylococcus aureus (MRSA) appears to be driving an increase in the number of people hospitalized with skin and soft tissue infections, researchers found.

From 2000 through 2004, the number of people admitted for MRSA and other skin and soft tissue infections increased by 28.9%, according to Marcus Zervos, MD, of Henry Ford Health System in Detroit, and colleagues.

The results are consistent with recently reported increases of S. aureus infections, particularly those caused by the methicillin-resistant variety, they reported in the September issue of Emerging Infectious Diseases.

Community-acquired MRSA accounts for 14% of invasive infections overall and 59% of skin and soft tissue infections treated at emergency departments, they said.

Two main factors drive hospitalization, Zervos said.

"One is how sick the patient is and the second is if we're dealing with antibiotic-resistant bacteria like MRSA there are relatively limited treatment options and that results in hospitalization," he said.

Before 2000, MRSA skin infections outside of healthcare settings were relatively rare, but reports of invasive S. aureus infections and deaths prompted Zervos and his colleagues to look at hospitalizations.

Using data from the U.S. Healthcare Cost and Utilization Project -- National Inpatient Sample, the researchers identified a rise in admissions for skin and soft tissue infections that they believe to be largely the result of an increase in MRSA infections.

The estimated total number of annual admissions rose from 674,939 in 2000 to 869,777 in 2004.

The increase was most pronounced in people younger than 65 (37% versus 14% for older individuals), in urban rather than rural hospitals (32% versus 11%), and in patients with superficial rather than deeper or healthcare-related infections (33% versus 24%).

Over the same time period, hospitalizations for pneumonia -- included for comparison because no trends were expected -- declined slightly.

The findings, Zervos said, highlight the importance of preventing the spread of MRSA.

Measures include avoiding unnecessary antibiotic use, regular hand washing, keeping dressings on skin wounds covered, and avoiding situations where the bacteria are present. For example, sporting equipment should not be shared, he said.

"If we can work to do a better job at prevention, I think that'll have an important impact, not only on mortality and on morbidity but also on cost of medical care," he said.

The study was funded by Astellas Pharma US.

One of Dr. Zervos' co-authors is medical director at Policy Analysis. The study authors made no other disclosures.